<UserControl 
    x:Class="SimpleSilverlight.Page"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    xmlns:cmd="clr-namespace:Onyx.Command;assembly=OnyxSL"
    xmlns:onyx="clr-namespace:Onyx.Windows;assembly=OnyxSL"
    xmlns:ui="clr-namespace:SimpleSilverlight" 
    onyx:View.Model="SimpleSilverlight.MainWindowViewModel"
    Width="400" Height="300" >

    <Grid x:Name="LayoutRoot" Background="White">
        <Button 
            x:Name="TestButton"
            x:FieldModifier="private"
            VerticalAlignment="Top" 
            cmd:ButtonBaseExtensions.Command="{Binding TestMessageDisplay}" 
            Content="Test" />
    </Grid>
</UserControl>